NGC 7678

NGC 7678
NGC 7678 by the Hubble Space Telescope
Observation data (J2000 epoch)
ConstellationPegasus
Right ascension23h 28m 27.9s[1]
Declination+22° 25′ 16″[1]
Redshift0.011638 ± 0.000005 [1]
Heliocentric radial velocity3,489 ± 1 km/s[1]
Distance132 ± 34.9 Mly (40.38 ± 10.69 Mpc)[1]
Apparent magnitude (V)11.8[2]
Characteristics
TypeSAB(rs)c [1]
Apparent size (V)2.17′ × 1.67′[1]
Notable featuresStarburst galaxy
Other designations
UGC 12614, VV 359, Arp 28, CGCG 476-045, MCG +04-55-017, PGC 71534[1]

NGC 7678 is an intermediate spiral galaxy located in the constellation Pegasus. It is located at a distance of about 130 million light years from Earth, which, given its apparent dimensions, means that NGC 7678 is about 95,000 light years across. It was discovered by William Herschel on September 15, 1784.[3]

Characteristics

NGC 7678 is a grand design spiral galaxy with two arms, from which the south arm is more prominent, and as a result the galaxy is asymmetrical. It was initially considered to that the asymmetry was the caused by a different galaxy interacting with NGC 7678 but further observations reveal that this is not the case.[4] The galaxy is featured in Arp's Atlas of Peculiar Galaxies as number 28, in the category "One heavy arm".[5]

The galaxy has a small nucleus and a weak bar.[4] The galaxy had been identified based on the spectral emission as a type 2 Seyfert galaxy,[6] but the ratio of [NII]λ 6583/H-alpha indicates it is an HII region or a low-ionization nuclear emission-line region,[4] with the HII region classification being supported by the λ6584/Hα and λ5007/Hβ ratios.[7]

Many large HII regions are visible at the southern arm.[4] Ten giant HII regions have been detected in NGC 7678, with the largest having a mass of 107 M☉. These regions are places of active star formation and contain star clusters.[8] The largest HII region in the southern arm could be the relic of a satellite galaxy that merged with NGC 7678 and caused the starburst activity.[4] The total star formation rate of the galaxy is estimated to be 3.8 M☉ per year based on corrected Paα emission or 7.4 M☉ per year based on infrared emission.[9]

Four supernovae have been detected in NGC 7678: SN 1997dc (type Ib, mag. 18.3),[10] SN 2002dp (type Ia, mag. 15.1),[11] SN 2009ga (type II-P, mag. 16.2),[12] and SN 2021qvr (type II, mag. 17.7).[13][14][15]

Nearby galaxies

NGC 7678 is an isolated galaxy in the kiloparsec scale.[16] Garcia indetified the galaxy as member of a galaxy group known as LGG 474. Other members of the group include NGC 7673, NGC 7677, and NGC 7664.[17]

References

  1. ^ a b c d e f g h "NASA/IPAC Extragalactic Database". Results for NGC 7678. Retrieved 2016-01-18.
  2. ^ "Revised NGC Data for NGC 7678". spider.seds.org. Retrieved 25 November 2018.
  3. ^ Seligman, Courtney. "NGC 7678 (= Arp 28)". Celestial Atlas. Retrieved 19 November 2018.
  4. ^ a b c d e Ann, Hong-Bae; Kim, Jeong-Mi (1 October 1996). "Photometry and Spectroscopy of the Spiral Galaxy NGC 7678". Journal of Korean Astronomical Society. 29 (2): 255–268. Bibcode:1996JKAS...29..255A. ISSN 1225-4614.
  5. ^ "HubbleSite: A Peculiar Sight". hubblesite.org. March 22, 2021.
  6. ^ Kazarian, M. A. (1 January 1993). "Spectrophotometric investigation of two Seyfert galaxies". Astrofizika. 36: 353–361. Bibcode:1993Afz....36..353K.
  7. ^ Gonçalves, A. C.; Véron, P.; Véron-Cetty, M.-P. (January 1998). "Miscellaneous observations of active galactic nuclei. II". Astronomy and Astrophysics Supplement Series. 127 (2): 107–115. arXiv:astro-ph/9705034. Bibcode:1998A&AS..127..107G. doi:10.1051/aas:1998336. S2CID 55269918.
  8. ^ Gusev, A. S.; Sakhibov, F.; Piskunov, A. E.; Kharchenko, N. V.; Bruevich, V. V.; Ezhkova, O. V.; Guslyakova, S. A.; Lang, V.; Shimanovskaya, E. V.; Efremov, Y. N. (11 April 2016). "A spectral and photometric study of 102 star-forming regions in seven spiral galaxies". Monthly Notices of the Royal Astronomical Society. 457 (3): 3334–3355. arXiv:1601.07470. doi:10.1093/mnras/stw212.
  9. ^ Tateuchi, Ken; Konishi, Masahiro; Motohara, Kentaro; Takahashi, Hidenori; Kato, Natsuko Mitani; Kitagawa, Yutaro; Todo, Soya; Toshikawa, Koji; Sako, Shigeyuki; Uchimoto, Yuka K.; Ohsawa, Ryou; Asano, Kentaro; Ita, Yoshifusa; Kamizuka, Takafumi; Komugi, Shinya; Koshida, Shintaro; Manabe, Sho; Nakamura, Tomohiko; Nakashima, Asami; Okada, Kazushi; Takagi, Toshinobu; Tanabé, Toshihiko; Uchiyama, Mizuho; Aoki, Tsutomu; Doi, Mamoru; Handa, Toshihiro; Kawara, Kimiaki; Kohno, Kotaro; Minezaki, Takeo; Miyata, Takashi; Morokuma, Tomoki; Soyano, Takeo; Tamura, Yoichi; Tanaka, Masuo; Tarusawa, Ken'ichi; Yoshii, Yuzuru (26 February 2015). "GROUND-BASED Paα NARROW-BAND IMAGING OF LOCAL LUMINOUS INFRARED GALAXIES. I. STAR FORMATION RATES AND SURFACE DENSITIES". The Astrophysical Journal Supplement Series. 217 (1): 1. arXiv:1412.3899. Bibcode:2015ApJS..217....1T. doi:10.1088/0067-0049/217/1/1. S2CID 119278582.
  10. ^ "SN 1997dc". Transient Name Server. IAU. Retrieved 18 August 2024.
  11. ^ "SN 2002dp". Transient Name Server. IAU. Retrieved 18 August 2024.
  12. ^ "SN 2009ga". Transient Name Server. IAU. Retrieved 18 August 2024.
  13. ^ "List of Supernovae". www.cbat.eps.harvard.edu. Central Bureau for Astronomical Telegrams. Retrieved 8 July 2023.
  14. ^ "Bright Supernova pages - Most prolific galaxies". www.rochesterastronomy.org. Retrieved 8 July 2023.
  15. ^ "SN 2021qvr". Transient Name Server. IAU. Retrieved 18 August 2024.
  16. ^ Koulouridis, Elias; Chavushyan, Vahram; Plionis, Manolis; Krongold, Yair; Dultzin-Hacyan, Deborah (November 2006). "A Three-dimensional Study of the Local Environment of Bright IRAS Galaxies: The Active Galactic Nucleus–Starburst Connection". The Astrophysical Journal. 651 (1): 93–100. arXiv:astro-ph/0606365. Bibcode:2006ApJ...651...93K. doi:10.1086/507070. S2CID 15469642.
  17. ^ Garcia, A. M. (1 July 1993). "General study of group membership. II. Determination of nearby groups". Astronomy and Astrophysics Supplement Series. 100: 47–90. Bibcode:1993A&AS..100...47G. ISSN 0365-0138.
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